The average (arithmetic mean) of a list of numbers is what percent of the sum of the numbers?
(1) There are 8 numbers in the list.
(2) The sum of the numbers in the list is 100.
I thought the ans was E which doesn't seem to be the correct OA?
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avg = sum/nrahul26 wrote:The average (arithmetic mean) of a list of numbers is what percent of the sum of the numbers?
(1) There are 8 numbers in the list.
(2) The sum of the numbers in the list is 100.
I thought the ans was E which doesn't seem to be the correct OA?
From S1, n=8, we have:
avg = sum/8
If the average is 1/8th of the sum, it's equal to 12.5% of the sum, and Statement 1 is sufficient.
________
I've ignored a small technicality above; as worded, the question does not exclude the possibility that the sum of the numbers is zero. Of course, if the sum of the numbers is zero, the question doesn't make any sense (it becomes 'zero is what percent of zero?') and if the above were a real GMAT question, the question would definitely include the restriction that all of the numbers in the list are positive.
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aj5105
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That's cool Ian.
Ian Stewart wrote:avg = sum/nrahul26 wrote:The average (arithmetic mean) of a list of numbers is what percent of the sum of the numbers?
(1) There are 8 numbers in the list.
(2) The sum of the numbers in the list is 100.
I thought the ans was E which doesn't seem to be the correct OA?
From S1, n=8, we have:
avg = sum/8
If the average is 1/8th of the sum, it's equal to 12.5% of the sum, and Statement 1 is sufficient.
________
I've ignored a small technicality above; as worded, the question does not exclude the possibility that the sum of the numbers is zero. Of course, if the sum of the numbers is zero, the question doesn't make any sense (it becomes 'zero is what percent of zero?') and if the above were a real GMAT question, the question would definitely include the restriction that all of the numbers in the list are positive.
